1. Field of the Invention
The present invention generally relates to recording media recorded with a program for detecting database operation timing such as timing of performing page relocation in a database or timing of performing the capacity expansion of the database, methods of detecting database operation timing, and apparatuses for detecting database operation timing, and more particularly to a recording medium recorded with a program for detecting database operation timing, a method of detecting database operation timing, and an apparatus for detecting database operation timing which program, method, and apparatus detect timing of performing page relocation in a database or timing of performing the capacity expansion of the database.
A network structure database employs prime pages and overflow pages, which are used when the prime pages have no space, so as to enable a high-speed access thereto.
Once on-line operations start, such a database requires page (record) relocation since record addition, deletion, or update creates fragmentary spaces in the prime and overflow pages. Further, if the database seems to run out of its capacity, the capacity of the database has to be expanded.
Timing of performing the page relocation in or the capacity expansion of such a database should be detected accurately with a minimum influence on the on-line operations.
2. Description of the Related Art
Conventionally, a system administrator has judged the necessity of page relocation in or the capacity expansion of a database based on the analysis results of a job executed to recognize the storage condition of data in the database, that is, based on analysis results as to whether the number of regions that are not reusable due to fragmentation is large or small.
Then, if the system administrator determines, based on the analysis results, that the number of reusable regions is so large that the database requires page relocation, the system administrator performs the page relocation during a jog execution by activating a program configured in accordance with an invention disclosed in Japanese Laid-Open Patent Application No. 6-110743.
Further, if the system administrator determines, based on the analysis results, that such page relocation does not allow the database to store further data, the system administrator activates a program for implementing the capacity expansion of the database so as to expand the capacity of the database.
Thus, according to a conventional method, the system administrator judges the necessity of page relocation in or the capacity expansion of the database by executing the job for recognizing the data storage condition of the database. This job is executed at a timing when the on-line operations are stopped.
The job executed at this timing is input to and output from the entire database so as to recognize the data storage condition of the database.
According to such a conventional method, however, the on-line operations should be stopped in order to judge the necessity of the page relocation in or the capacity expansion of the database, thus causing a problem that a request for an on-line operation hour extension cannot be answered. Especially, this is a problem in 24-hour continuous on-line operations.
Further, according to the conventional method, the system administrator, based on her/his experience, judges the necessity of the page relocation in or the capacity expansion of the database, referring to the analysis results of the above-described job.
However, this does not mean that the page relocation in or the capacity expansion of the database is always performed at an appropriate timing.
Therefore, in the worst case, the conventional method causes the shortage of the capacity of the database so that an on-line program is prevented from storing records to end abnormally.